The tank was supposed to have 4 diesel engines from the Valentine tanks with 131hp each, together producing 624hp. Each engine was placed in one corner of the hull. The center of the hull was empty and formed a passage from the driver's compartment to the combat compartment and read compartment. Each engine had a clutch, a transmission, the gear was coupled thru a conical pairing with a transverse shaft. There were two such shafts - one for each side of the tank. These shafts were connected to the side friction clutches. There were 4 such clutches and 4 drive wheels.
The engines, clutches and drivewheels were synchronised and controlled by the driver. Damaged engines can be switched off by the driver. The vehicle was designed so that it could move with only one engine working.

So, Listy, what was that, some Churchill? Pasholok mentions "it's too early for AT-1"

riiiight, "real historical document" suddenly discovered by some soviet game developer who supposedly has access to USSR's confidential military archives - that and previous "real historical documents" iare as real as Boris Berezovsky's suicide

The USSR's old archives are publically accesible now. In many respects, it's very similar to the US National Archives. Everything's hard to find, some sections are still classified, but the archives themselves are accesible to anybody.

Each engine with a firewall adding to the weight and taking up much more space inside the tank than a single engine of similar total power. Each engine requiring separate maintenance and multiple drive shafts going everywhere again taking up space, adding complexity and causing vibration. When it works it would have two pairs of coupled engines and if one of a pair was not running well there would be added stress on the already complex drive train and if one engine gets hit or locks up the shock will travel down the drive chain and if lucky will only destroy a clutch but could also damage the transmission and the other engine. This approach leads to a bigger heavier or less well armoured tank that on that ground alone defeats the object

In WWII there were a lot of crackpot schemes to provide more power using readily available coupled engines every one of them ended up with equipment that was a waste of resources and more dangerous to the crews than to the enemy.

Even using hydraulic transmission to mechanically isolate the engines and remove the drive train issues would make this a dead end project.

Didn't the Churchill have Twin Bedfords ? I may be talking out of my (ignorant but interested) hat, but I was of the belief that twin configurations generated more torque than equivalent powered single engines and that was one of the reasons that the Churchill was so effective at climbing hills on even poor ground (such as sand). Ground pressure and track designs also being important.

Not quite, it was two straight six cylinder heads driving the same crankshaft and operated as one 12-cylinder engine. To confuse matters it was call "twin six" or a "Bedford horizontally opposed twin-six petrol engine" it was in face a flat 12. The straight six is a configuration that leads to a very vibration free and smooth running engine with less losses to unbalanced forces so a flat 12 would have much the same benefits. With six cylinders fireing for each rev of the engine there would be little drop of in torque at low speeds. But I think the climbing performance of the Churchill was down to the fact that it was underpowered and so the low gears needed to have a high gearing at the low end just to get it going with the benefit that the engine could be reving at its best power output speed and the tank in low gear would be moving at 3 MPH thus providing a lot of traction.

The main problem I have with this document is there is no date time stamp on it and where does it comes from? Could this be some document schemed up to satisfy Stalin? Yet on the other hand the Brits had some weird ideas during the war...

Any idea of the manufacturer? It is very unusual for the design ethos of the time so would not have originated from the Armour Committee so I am thinking it may well be an Old Gang idea as they came up with the TOGs. William Fosters of Lincoln have an untraced reference to a tank designed for Italy from before the war so although it's not likely to be this one its certainly not impossible.-Vollketten